Method, apparatus and system for virtual network configuration and partition handover

ABSTRACT

A method, apparatus and system for virtual network configuration and partition handover are provided. The virtual network configuration method includes the following steps: The serving edge device obtains a target virtual network identifier and a corresponding interface identifier, uses the target virtual network identifier and the corresponding interface identifier to generate a Layer-2 Control (L2C) protocol packet, and sends out the L2C protocol packet; the communication proxy device that receives the L2C protocol packet obtains the target virtual network identifier and the corresponding interface identifier from the L2C protocol packet, and sets up a mapping relation between a target virtual network and an interface.

This application is a continuation of International Application No.PCT/CN2008/073250, filed on Nov. 28, 2008, which claims priority toChinese Patent Application No. 200710077481.6, filed on Nov. 30, 2007,both of which are hereby incorporated by reference in their entireties.

FIELD OF THE INVENTION

The present invention relates to network communication technologies, andin particular, to a method, apparatus, and system for virtual networkconfiguration and partition handover.

BACKGROUND OF THE INVENTION

Network providers provide Virtual Local Area Network (VLAN)/VirtualPrivate Network (VPN) connections for Service Providers (SPs) such as anInternet Service Provider (ISP) so that a user can be connected to thesubscribed SP system through a corresponding VLAN/VPN transmissionchannel. However, to implement VLAN/VPN connections in a fixed accessnetwork, it is necessary to configure the relation between the VLAN/VPNID and the user on the access network device.

In the process of implementing the present invention, the inventor findsthat: The relation between the VLAN ID and the user on the fixed accessnetwork in the prior art is configured statically through the networkmanagement system of the access network itself, namely, configuredbefore the user is connected. The configuration mode is defective in thefollowing aspects:

1. When a nomadic user moves to a new network, because the new fixedaccess network has no VLAN ID corresponding to the nomadic user, thestatic configuration through the network management system of the newfixed access network does not support dynamic configuration of thenomadic or mobile user, and does not support the virtual network accessof the nomadic or mobile user; and

2. When the user needs to be handed over from the same physical/virtualport to a new service/SP network dynamically, because the staticconfiguration mode of the network management system does not support thedynamic configuration mode of the service/SP, the user cannot be handedover to the new service/SP network dynamically.

SUMMARY OF THE INVENTION

A virtual network configuration method provided in an embodiment of thepresent invention includes the following:

by a serving edge device, obtaining a target virtual network identifierand a corresponding interface identifier, using the target virtualnetwork identifier and the corresponding interface identifier togenerate a Layer-2 Control (L2C) protocol packet, and sending out theL2C protocol packet; and

by a communication proxy device that receives the L2C protocol packet,obtaining the target virtual network identifier and the correspondinginterface identifier from the L2C protocol packet, and setting up amapping relation between a target virtual network and an interface.

A communication system provided in an embodiment of the presentinvention includes the following:

a serving edge device, adapted to: obtain a target virtual networkidentifier and a corresponding interface identifier in an L2C protocolpacket, generate an L2C protocol packet, and send the generated L2Cprotocol packet to an access network device; and

a communication proxy device, adapted to: receive the L2C protocolpacket, obtain the target virtual network identifier and thecorresponding interface identifier from the L2C protocol packet, and setup a mapping relation between an interface corresponding to theinterface identifier and a target virtual network.

A communication proxy apparatus provided in an embodiment of the presentinvention includes the following:

a receiving unit, adapted to receive an L2C protocol packet that carriesa target virtual network identifier and a corresponding interfaceidentifier;

an obtaining unit, adapted to parse the L2C protocol packet to obtainthe target virtual network identifier and the corresponding interfaceidentifier from the packet;

a storing unit, adapted to: store information about a mapping relationbetween an interface and a virtual network, where the information aboutthe mapping relation includes the virtual network identifier and theinterface identifier; and

a configuring unit, adapted to modify the information about the mappingrelation in the storing unit according to the obtained target virtualnetwork identifier and corresponding interface identifier.

Through the technical solution under the present invention, dynamicconfiguration of nomadic access is provided for nomadic users, and it isconvenient for a user to perform handover from the virtual network ofone service provision system to the virtual network of another servicesystem.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a network communication device provided in an embodiment ofthe present invention;

FIG. 2 shows a serving edge device provided in an embodiment of thepresent invention;

FIG. 3 shows a nomadic scenario provided in an embodiment of the presentinvention;

FIG. 4 is a flowchart of a nomadic scenario provided in an embodiment ofthe present invention;

FIG. 5 shows a first service/SP handover scenario provided in anembodiment of the present invention;

FIG. 6 is a flowchart of a service/SP handover scenario provided in anembodiment of the present invention;

FIG. 7 shows a second service/SP handover scenario provided in anembodiment of the present invention;

FIG. 8 is a service/SP handover flowchart of a physical partition listin an embodiment of the present invention;

FIG. 9 is a service/SP handover flowchart of a physical ACL in anembodiment of the present invention;

FIG. 10 shows a third service/SP handover scenario provided in anembodiment of the present invention;

FIG. 11 is a service/SP handover flowchart of a logical partition listin an embodiment of the present invention;

FIG. 12 is a service/SP handover flowchart of a physical ACL in anembodiment of the present invention;

FIG. 13 shows a fourth service/SP handover scenario provided in anembodiment of the present invention;

FIG. 14 shows a fifth service/SP handover scenario provided in anembodiment of the present invention; and

FIG. 15 shows a sixth service/SP handover scenario provided in anembodiment of the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

First, the general embodiments of the present invention are describedbelow.

A virtual network configuration method provided in an embodiment of thepresent invention includes the following:

A serving edge device obtains a target virtual network identifier and acorresponding interface identifier, uses the target virtual networkidentifier and the corresponding interface identifier to generate an L2Cprotocol packet, and sends out the L2C protocol packet; a communicationproxy device (a device on the access network, for example, an L2C proxy)that receives the L2C protocol packet obtains the target virtual networkidentifier and the corresponding interface identifier from the L2Cprotocol packet, and sets up a mapping relation between a target virtualnetwork and an interface. Through the technical solution under thepresent invention, the virtual network interface parameter informationcan be configured dynamically, and then the packet between the accessdevice and the service provision device is carried through thecorresponding virtual network channel. Therefore, it is convenient tohand over the services for the nomadic users and the users. The servicehandover of the user includes the service handover selected by the user,and the service handover selected by the service provision system.

In the process of authenticating the nomadic user, the serving edgedevice obtains the target virtual network identifier corresponding tothe nomadic user and the interface identifier of the interface accessedby the nomadic user.

When the user selects a target service or is re-authenticated, theserving edge device obtains the target virtual network identifierselected by the user and the corresponding interface identifier.

When the target service provision device selects the target multicastvirtual network for handover, the serving edge device obtains the targetvirtual network identifier and the corresponding interface identifier.

The communication proxy device deletes the physical interfacecorresponding to the interface identifier from the physical interfacepartition corresponding to the current virtual network identifier; andadds the physical interface to the physical interface partitioncorresponding to the target virtual network identifier. The physicalinterface partition in the context includes at least one physicalinterface.

The communication proxy device deletes the virtual interfacecorresponding to the interface identifier from the virtual interfacepartition corresponding to the current virtual network identifier; andmodifies the information about the mapping relation between the physicalinterface partition corresponding to the target virtual networkidentifier and the virtual interface partition. The virtual interface ofthe context is an interface after the physical interface correspondingto the access device is mapped; the virtual interface partition includesat least one virtual interface. In the context, the reciprocallycorresponding physical interface partition and virtual interfacepartition have corresponding physical interfaces and virtual interfaces.The mapping relation between the physical interface and the virtualinterface may be a one-to-one relation or a many-to-one relation.

After the mapping relation between the target virtual network and theinterface is set up, the communication proxy device returns an L2Cprotocol response packet, indicating that the configuration is complete.

The communication proxy device and the access device are set in the samephysical entity; or the communication proxy device is set in an accessconvergence device, or the communication proxy device and the servingedge device are set in the same physical entity.

The interface is a physical port, and the information about the mappingrelation between the target virtual network and the interface includesthe target virtual network identifier and the corresponding physicalport identifier; or

The interface is a physical access circuit, and the information aboutthe mapping relation between the target virtual network and theinterface includes the physical access control information and thecorresponding physical Access Circuit Identifier (ACI); or

The interface is a virtual port, and the information about the mappingrelation between the target virtual network and the interface includes avirtual target virtual network identifier and the corresponding virtualport identifier; or a virtual target virtual network identifier and thecorresponding information about the mapping relation between the virtualport and the physical port; or

The interface corresponding to the access device is a virtual accesscircuit, and the information about the mapping relation between thetarget virtual network and the interface includes virtual target accesscontrol information and the corresponding virtual ACI, or virtual targetaccess control information and the corresponding information about themapping relation between the virtual port and the physical port, wherethe virtual network may be a VLAN or a VPN.

Another virtual network partition handover method provided in anembodiment of the present invention includes the following:

The communication proxy receives an L2C protocol packet, and obtains atarget virtual network identifier and a corresponding interfaceidentifier in the L2C protocol packet; the communication proxy devicedeletes the physical interface corresponding to the interface identifierfrom the physical interface partition corresponding to the currentvirtual network identifier; and adds the physical interface to thephysical interface partition corresponding to the target virtual networkidentifier.

The physical interface may be a physical port and/or a physical accesscircuit, and the virtual network may be a VLAN and/or a VPN.

Another virtual network partition handover method provided in anembodiment of the present invention includes the following:

The communication proxy receives an L2C protocol packet, and obtains atarget virtual network identifier and a corresponding interfaceidentifier in the L2C protocol packet; the communication proxy devicedeletes the virtual interface corresponding to the interface identifierfrom the virtual interface partition corresponding to the currentvirtual network identifier; and modifies the information about themapping relation between the physical interface partition correspondingto the target virtual network identifier and the virtual interfacepartition.

The physical interface may be a physical port and/or a physical accesscircuit, and the virtual interface may be a virtual interface and/or alogical access circuit; and the virtual network may be a VLAN and/or aVPN.

A communication system provided in an embodiment of the presentinvention includes:

a serving edge device, adapted to: obtain a target virtual networkidentifier and a corresponding interface identifier in an L2C protocolpacket, generate an L2C protocol packet, and send the generated L2Cprotocol packet to an access network device; and a communication proxydevice, adapted to: receive the L2C protocol packet, obtain the targetvirtual network identifier and the corresponding interface identifierfrom the L2C protocol packet, and set up a mapping relation between aninterface corresponding to the interface identifier and a target virtualnetwork.

A communication proxy apparatus (L2C proxy) is provided in an embodimentof the present invention. As shown in FIG. 1, the L2C proxy 110includes:

a receiving unit (for example, an upstream packet forwarding unit 111),adapted to receive an L2C protocol packet that carries a target virtualnetwork identifier and a corresponding interface identifier;

an obtaining unit (for example, the obtaining unit 128 in FIG. 1),adapted to parse the L2C protocol packet to obtain the target virtualnetwork identifier and the corresponding interface identifier from thepacket;

a storing unit (for example, the storing unit 124 in FIG. 1), adaptedto: store information about a mapping relation between an interface anda virtual network, where the information about the mapping relationincludes the virtual network identifier and the interface identifier;and

a configuring unit (for example, the configuring unit 130 in FIG. 1),adapted to modify the information about the mapping relation in thestoring unit according to obtained target virtual network identifier andcorresponding interface identifier.

The storing unit records at least one mapping relation partitioninformation unit, and each mapping relation partition information unitcorresponds to a virtual network, and records the virtual networkidentifier and the corresponding interface partition information. Theconfiguring unit deletes the interface information corresponding to theinterface identifier from the mapping relation partition informationunit corresponding to the current virtual network identifier, and addsthe interface information corresponding to the interface identifier tothe mapping relation partition information unit corresponding to thetarget virtual network identifier.

The interface is a physical interface, and the mapping relationpartition information unit records a virtual network identifier and thecorresponding physical interface information; or

The interface is a virtual interface, and the mapping relation partitioninformation unit records a logical virtual network identifier and thecorresponding mapping relation between the virtual interface and thephysical interface.

The communication proxy apparatus further includes: a port mapping unit,adapted to perform conversion between the physical interface and thelogical port for the received packet according to the information aboutthe mapping relation between the physical interface and the virtualinterface.

The communication proxy apparatus further includes: a matching unit,adapted to: check whether the target virtual network identifier matchesthe current virtual network identifier; and, if they do not match,notify the configuring unit to start configuration.

Note that the communication proxy apparatus (L2C proxy) in the contextmay be set in an access convergence device of the access network, or setin an access node, for example, a Digital Subscriber Line AccessMultiplexer (DSLAM) of a Digital Subscriber Line (DSL) system. Thevirtual network may be a VLAN (virtual networks include multicastVLANs), or a VPN. The communication proxy device uses a Layer 2 ControlProtocol (L2CP) to control plenty of access nodes under it through an IPedge node such as a Broadband Remote Access Server (BRAS) or a BroadbandNetwork Gateway (BNG). The communication proxy apparatus (L2C Proxy) iscapable of topology discovery, line configuration, line test, andmulticast control. The L2C proxy performs physical partitioning for thephysical interfaces (for example, physical ports of the DSL, multicastaccess circuits) of the DSLAM according to the SP (for example, the ISP)or access network. The L2C proxy introduces “port mapping units”,including “virtual partition list” and “port mapping function”. The“virtual partition list” is mapped according to the ISP or accessnetwork. The one-to-one mapping relation between the “virtual partitionlist” and the “physical partition list” is accessed and managed by thecorresponding ISP through an Interworking Function (IWF) unit by meansof L2C messages, and the L2C messages are filtered, detected, convergedand forwarded. The IWF may filter, detect, converge and forward the L2Cmessages according to the ISP or access network, including: receivingthe packet from the ISP, determining the corresponding access networkaccording to the ISP that sends the packet, and forwarding the receivedpacket to the access network; receiving the packet from the accessnetwork, determining the corresponding ISP according to the accessnetwork that sends the packet, and forwarding the received packet to theISP. Therefore, it is necessary to save the mapping relation between theISP and the access network on the IWF, and maintain the peer informationon the access network and the ISP respectively, for example, maintainthe physical port information of the access network on the ISP so thatthe ISP can transmit information to the corresponding access network.

A network communication device provided in an embodiment of the presentinvention includes:

a communication interface, adapted to communicate with other networkcommunication devices, and receive and send packets.

The network communication devices include the communication proxyapparatus mentioned above.

The communication network device is a DSL access device, or an accessconvergence device, or a broadband access server, or a broadband bordergateway.

FIG. 2 shows another serving edge device 200 provided in an embodimentof the present invention. The serving edge device 200 includes anupstream communication interface 201, a downstream communicationinterface 202, an upstream packet forwarding unit 203 and a downstreampacket forwarding unit 204.

The upstream communication interface 201 is connected to a serviceprovision device, and the downstream communication interface 202 isconnected to an access convergence device or an access device.

The downstream packet forwarding unit 204 is adapted to receive and sendthe packet from the access device through the downstream communicationinterface 202. The upstream packet forwarding unit 203 is adapted toreceive and send the packet from the service provision device throughthe upstream communication interface 201.

Through a service selecting module 212 or an L2C protocol module 213,the obtaining module 214 may obtain the target virtual networkidentifier and the interface identifier corresponding to the accessdevice from the packet exchanged between the upstream packet forwardingunit 203 and the downstream packet forwarding unit 204. The obtainingmodule 214 may also obtain the virtual network identifier dynamically(not illustrated in the figure).

The configuring unit 216 uses the information obtained by the obtainingunit to generate an L2C protocol packet, and sends the generated packetto the corresponding device through the downstream packet forwardingunit 204.

Optionally, the serving edge device 200 may include an authenticatingmodule 211 which authenticates the user who attempts to access theservice provision device or select a handover service.

First Embodiment

The application scenario of the first method of the present invention isa nomadic scenario, as shown in FIG. 3.

Each user corresponds to a port, which is either a physical port or avirtual port. The port may be sorted by: physical line such as DSL andVirtual Channel (VC), by layer-2 information (for example, VLAN ID,Ethernet priority, MAC address), or by quintuplet information (forexample, source IP address, destination IP address, source port,destination port, and protocol type).

As shown in FIG. 3, a local user accesses the network through port 1,and the mapping relation between port 1 corresponding to the local userand the VLAN/VPN ID 1 is already configured on the access network.Therefore, the local user accesses the network from the correspondingport 1. The access network maps port 1 to the corresponding layer-2 VLANor VPN channel according to the mapping relation, and port 1 isconnected to the access network.

As shown in FIG. 3, the nomadic user accesses the network through port2. No mapping relation between port 2 corresponding to the nomadic userand the VLAN/VPN ID2 is configured on the access network. In this case,the IP edge node (such as the BNG and BRAS) delivers the mappingrelation between port 2 corresponding to the nomadic user and theVLAN/VPN ID2 to the access network dynamically through an L2C mechanism.Therefore, the nomadic user accesses the network through thecorresponding port 2, and the access network may map port 2 to thecorresponding VLAN or VPN channel according to the obtained mappingrelation between port 2 and the VLAN/VPN ID2, and port 2 is connected tothe access network.

As shown in FIG. 4, the detailed process is as follows:

Step S401: The nomadic user is authenticated through an IP edge.

The IP edge may obtain the port corresponding to the nomadic user fromthe authentication process. For example, the access network may providethe intermediate relay function, and the port information correspondingto the nomadic user is inserted into the PPPoE tag or DHCP Option.

Step S402: After the nomadic user is authenticated successfully, the IPedge obtains the profile of the nomadic user from the authenticationresult. The profile includes a VLAN/VPN ID. The VLAN/VPN ID may be acompletely new ID allocated dynamically; and the VLAN ID may be acustomer tag (C-Tag), a service tag (S-Tag), or a combination thereof.

Step S403: The IP edge binds the port corresponding to the nomadic userto the VLAN/VPN ID, sets up a mapping relation between the port and theVLAN/VPN ID, and delivers the mapping relation to the correspondingaccess network dynamically through the L2C protocol.

Step S404: The access network receives the L2C protocol packet from theIP edge, parses the packet to obtain the mapping relation between theport and the VLAN/VPN ID, and records the mapping relation.

Step S405: The nomadic user sends a user data packet through thecorresponding port. The data packet includes port information.

Step S406: The access network queries the list of mapping relationsbetween the port and the VLAN/VPN ID according to the port informationin the data packet, obtains the VLAN/VPN ID corresponding to the port,and maps the port to the VLAN/VPN channel corresponding to the VLAN/VPNID.

Step S407: The user data over the VLAN/VPN channel is obtained accordingto the mapping, and the user accesses the network.

Second Embodiment

The second embodiment of the present invention provides a service/SPhandover scenario, as shown in FIG. 5.

Each user corresponds to a port, and the mapping relation between theport corresponding to the user and the VLAN/VPN ID is already configuredon the access network. After the user accesses the network through port1, the user may query the mapping relation to obtain the correspondingVLAN/VPN ID according to the information about port 1. In this way, port1 is mapped to the layer-2 VLAN or VPN channel of the correspondingservice/SP, and the user accesses the corresponding service or SPnetwork.

When the user needs to be handed over from the same port 1 to a newservice/SP network dynamically, because no mapping relation between port1 corresponding to the user and the new VLAN/VPN ID is configured on theaccess network, the IP edge obtains such a mapping relation dynamicallythrough an L2C mechanism, and delivers the obtained mapping relation tothe corresponding access network. The access network receives andrecords the new mapping relation delivered by the IP edge. In this way,after the user accesses the network from the same port 1, the service ofport 1 is mapped to the corresponding layer-2 VLAN or VPN channel of thecorresponding service/SP under the new mapping relation, and the useraccesses the corresponding service or SP network.

As shown in FIG. 6, the process in this embodiment includes thefollowing steps:

Step S601: Before being handed over to the new service/SP network, theuser sends user data through the corresponding port 1.

Step S602: The access network parses the received user data packet toobtain the corresponding port, and, based on the port informationobtained from the parsed packet, searches the list of mapping relationsbetween the port and the VLAN/VPN ID to obtain the VLAN/VPN ID of theold service/SP corresponding to the port.

Step S603: The access network maps the service of port 1 to the VLAN/VPNID channel of the old service (or old SP) corresponding to port 1. TheVLAN/VPN channel of the old service (or old SP) carries the user data.In this way, the user accesses the old service or old SP network.

Step S604: The user selects a new service/SP network. Optionally, theuser needs to undergo a new user authentication process to set up a newsubscriber session.

Step S605: The IP edge obtains a user profile while the user selects theservice/SP. The user profile includes the VLAN/VPN ID of the new service(or new SP). The VLAN/VPN ID may be a wholly new ID allocateddynamically, and the VLAN ID may be an S-Tag.

Step S606: Through the L2C protocol, the IP edge delivers the newmapping relation between the port corresponding to the user and theVLAN/VPN ID of the new service (or new SP) to the corresponding accessnetwork.

Step S607: The mapping relation between the corresponding port 1 and theVLAN/VPN ID is set up or updated on the access network.

Step S608: The user sends the user data through the corresponding port.

Step S609: After the access network receives the user data packet, basedon the port information in the data packet, the access network searchesthe list of mapping relations between the port and the VLAN/VPN ID toobtain the VLAN/VPN ID of the new service (or new SP) corresponding toport 1.

Step S610: The access network maps the service of this port to theVLAN/VPN channel of the new service (or new SP). The VLAN/VPN channel ofthe new service (or new SP) carries the user data. In this way, the useraccesses the new service or new SP network.

Third Embodiment

In a multicast wholesale scenario, the retailer SP configures the AccessControl List (ACL) of the same DSLAM through a BNG by means of differentL2C connections. The IWF is designed for the IP edge node to performlayer-2 control for the access node. As shown in Table 1, the basicstructure of the ACL includes: ACI, multicast address, multicast sourceaddress (optional), and ACL attribute. The ACI is also known as anAccess Loop Identifier (ALI), for example, the physical portcorresponding to the DSL.

TABLE 1 Basic structure of an ACL Multicast Source ACI Multicast AddressAddress ACL Attribute Physical ACI 1 224.x.y.z a.b.c.d >allowed224.x1.y1.z1 a1.b1.c1.d1 >not allowed Physical ACI 2 . . .

The third embodiment of the present invention provides a secondservice/SP handover scenario, as shown in FIG. 7.

The domain between the access node and the IP edge node forms theVLAN/VPN domain of the service/SP, and each different service/SP has adifferent VLAN/VPN. In this embodiment, a physical partition list can bedivided on the access node according to the ISP, and a multicastphysical ACL can be divided on the access node according to the ISP. Thephysical partition list divided according to the ISP corresponds to themulticast physical ACL uniquely. Alternatively, the physical ACL is notdivided on the access network, namely, only one physical ACL exists onthe access node and includes all physical ACIs instead of being dividedaccording to the ISP.

In this embodiment, a virtual network partition handover methodincludes: A communication proxy device of an access device or an IP edgereceives an L2C protocol packet, and obtains the target virtual networkidentifier (the identifier of the virtual network that requirespartition handover) in the L2C protocol packet and the correspondinginterface identifier (physical interface identifier, for example, theACI in the physical port and the multicast VLAN). The communicationproxy device deletes the physical interface corresponding to theinterface identifier from the physical interface partition correspondingto the current virtual network identifier; and adds the physicalinterface information to the physical interface partition correspondingto the target virtual network identifier, where the physical interfacepartition includes at least one physical interface.

The service/SP handover process of the physical partition list is shownin FIG. 8.

Step S801: Before handover to the new service/SP network, a physicalpartition list is already set up on the access node. The physicalpartition list is divided according to the ISP, and the physical portcorresponding to the user belongs to physical partition list 1.

Step S802: The user selects a new service/SP network (such as ISP2).Optionally, the user needs to undergo a new user authentication processto set up a new subscriber session.

Step S803: The IP edge obtains a user profile while the user selects theservice/SP. The user profile includes the VLAN/VPN ID of the new service(or new SP). The VLAN/VPN ID may be a wholly new ID allocateddynamically, and the VLAN ID may be an S-Tag.

Step S804: Through the L2C protocol, the IP edge delivers the newmapping relation between the physical port corresponding to the user andthe VLAN/VPN ID of the new service (or new SP) to the correspondingaccess network.

Step S805: The access network queries the corresponding list of mappingrelations between the physical port and the VLAN/VPN ID. If the mappingrelation between the physical port and the VLAN/VPN ID changes, theaccess network starts handover of the service/SP.

Step S806: The access network deletes the corresponding physical portdelivered by the L2C protocol in S804 from the physical partition list1.

Step S807: According to the service/SP corresponding to the VLAN/VPN IDof the new service/SP, the corresponding physical port delivered throughthe L2C in S804 is added to the corresponding physical partition list(for example, physical partition list 2).

Step S808: The access network reports completion of the service/SPhandover to the IP edge through the L2C protocol.

The service/SP handover process of the physical ACL is shown in FIG. 9.

Step S901: Before handover to the new service/SP network, a physical ACLdivided according to the ISP is already set up on the access network.The physical ACI corresponding to the user belongs to physical ACL 1.

Step S902: The user selects a new service/SP network (such as ISP2).Optionally, the user needs to undergo a new user authentication processto set up a new subscriber session.

Step S903: The IP edge obtains a user profile while the user selects theservice/SP. The user profile includes the VLAN/VPN ID of the new service(or new SP). The VLAN/VPN ID may be a wholly new ID allocateddynamically, and the VLAN ID may be an S-Tag.

Step S904: Through the L2C protocol, the IP edge delivers the newmapping relation between the physical ACI corresponding to the user andthe VLAN/VPN ID of the new service (or new SP) to the correspondingaccess network.

Step S905: The access network queries the corresponding list of mappingrelations between the physical ACI and the VLAN/VPN ID. If the mappingrelation between the physical ACI and the VLAN/VPN ID changes, theaccess network starts handover of the service/SP.

Step S906: The access network deletes the corresponding physical ACIdelivered through the L2C protocol in S904 from the physical ACI 1.

Step S907: According to the service/SP corresponding to the VLAN/VPN IDof the new service/SP, the access network adds the correspondingphysical ACI delivered through the L2C protocol in S904 to thecorresponding physical ACI (for example, the physical ACI 2).

Step S908: The access network reports completion of the service/SPhandover to the IP edge through the L2C protocol.

Step S909: Through the L2C protocol, the IP edge configures themulticast address and the ACL attribute of the physical ACI newly addedin the physical ACL 2 of the access network.

Fourth Embodiment

The fourth embodiment of the present invention provides a thirdservice/SP handover scenario, as shown in FIG. 10.

Based on the L2C proxy, the VLAN/VPN domain between the access networkand the IP edge is divided into a first VLAN/VPN domain and a secondVLAN/VPN domain. That is, the domain between the access network and theL2C proxy is the first VLAN/VPN domain (namely, the access VLAN/VPNdomain), and the domain between the L2C proxy and the IP edge is thesecond VLAN/VPN domain (namely, the VLAN/VPN domain of the service/SP).Each different service/SP has a different VLAN/VPN. The L2C proxyrecords the virtual partition list divided according to the ISP. Thisvirtual partition list records the information about the mappingrelations between the virtual port and the VLAN/VPN ID. Besides, thevirtual partition list can be divided according to the ISP and recordedon the L2C proxy, and the multicast logical ACL can be divided accordingto the ISP on the access node. The virtual partition list dividedaccording to the ISP is similar to the multicast virtual ACL. It isappropriate if only one virtual ACL exists on the access node, and thisvirtual ACL includes all virtual ACIs and is not divided according tothe ISP. In the case of service/SP handover, only the virtual partitionlist needs to be handed over, and the physical partition list on theaccess node may keep unchanged, or even no physical partition listexists on the access node and the virtual partition list on the L2Cproxy works instead to implement the wholesale.

The service/SP handover process of the virtual partition list is shownin FIG. 11.

Step S1101: Before handover to the new service/SP network, a virtualpartition list is already set up on the access network. The virtualpartition list is divided according to the ISP, and the virtual portcorresponding to the user belongs to virtual partition list 1.

Step S1102: The user selects a new service/SP network (such as ISP2).Optionally, the user needs to undergo a new user authentication processto set up a new subscriber session.

S1103-S1107 are similar to S803-S807. The difference is that thephysical port and the physical partition list in FIG. 8 change to thevirtual port and virtual partition list in FIG. 11.

Step S1108: The access network modifies the port mapping list in theport mapping unit, and updates the mapping relation between the physicalport and the virtual port in the virtual port partition list. In thisembodiment, “mapping relation between the physical port and the virtualport of the virtual partition list 1” is modified to “mapping relationbetween the physical port and the virtual port of the virtual partitionlist 2”.

Step S1109: This step is the same as S808 in FIG. 8.

Similar to FIG. 9, FIG. 12 shows a service/SP handover process of thevirtual ACL.

Step S1201: The difference between FIG. 9 and FIG. 12 is that thephysical ACI and the physical ACL in FIG. 9 change to the virtual ACIand virtual ACL in FIG. 12.

Step S1202-1203 are the same as S902-903.

Step S1204-1207: The difference between S1204-1207 and S904-907 is thatthe physical ACI and the physical ACL in S904-907 change to the virtualACI and virtual ACL in this embodiment.

Step S1208: The access network modifies the port mapping list in theport mapping unit, and updates the mapping relation between the physicalACI and the virtual ACI in the virtual ACL. In this embodiment, “mappingrelation between the physical ACI and the virtual ACI of the virtual ACL1” is modified to “mapping relation between the physical ACI and thevirtual ACI of the virtual ACL 2”.

Step S1209 is the same as S908.

Step S1210: The difference between S1210 and S909 is that the physicalACI and the physical ACL in S909 change to the virtual ACI and virtualACL in S1210.

The fourth method application scenario of the present invention is afourth service/SP handover scenario, as shown in FIG. 13. FIG. 13differs from FIG. 10 in that: A remote access network is introduced, andthe L2C proxy is located on the remote access network. The process isthe same.

The fourth method application scenario of the present invention is thefifth and sixth service/SP handover scenarios, as shown in FIG. 14 andFIG. 15. FIG. 14 and FIG. 15 differ from FIG. 10 in that: The L2C proxyis set inside a BNG/BRAS, as shown in FIG. 14; or set inside the accessnetwork, as shown in FIG. 15. The process is the same.

In conclusion, through the embodiments of the present invention, theservice data can be configured dynamically in the access device and theSP system, and in particular, the port and the VLAN/VPN attributecorresponding to each SP system can be configured dynamically. Throughthe embodiments described above, when a nomadic user roams to a remotenetwork and wants to access the service of the home SP system, thenomadic user dynamically obtains the information about the mappingrelation between the VLAN/VPN network attribute of the home SP systemand the access port through the L2C function, thus overcoming theincapability of accessing the home SP system in the prior art. In theembodiments of the present invention, when a user is handed over from anSP system to a new SP system, the user dynamically obtains theinformation about the mapping relation between the access port and theVLAN/VPN network attribute of the new SP system through the L2Cfunction, and thus is handed over to the new SP system smoothly.

The above descriptions are merely exemplary embodiments of the presentinvention, but not intended to limit the scope of the present invention.Any modifications, variations or replacement that can be easily derivedby those skilled in the art should fall within the scope of the presentinvention. Therefore, the scope of protection of the present inventionis subject to the appended claims.

1. A virtual network configuration method, comprising: by a serving edgedevice, obtaining a target virtual network identifier and acorresponding interface identifier, using the target virtual networkidentifier and the corresponding interface identifier to generate aLayer-2 Control (L2C) protocol packet, and sending out the L2C protocolpacket; and by a communication proxy device that receives the L2Cprotocol packet, obtaining the target virtual network identifier and thecorresponding interface identifier from the L2C protocol packet, andsetting up a mapping relation between a target virtual network and aninterface.
 2. The configuration method of claim 1, comprising: by theserving edge device in a process of authenticating a nomadic user,obtaining the target virtual network identifier corresponding to thenomadic user and the interface identifier of the interface accessed bythe nomadic user; or by the serving edge device when the user selects atarget service and/or is re-authenticated, obtaining the target virtualnetwork identifier selected by the user and the corresponding interfaceidentifier; or by the serving edge device when a target serviceprovision device selects a target multicast virtual network forhandover, obtaining the target virtual network identifier and thecorresponding interface identifier.
 3. The configuration method of claim1, wherein the process of setting up the mapping relation between thetarget virtual network and the interface comprises: by the communicationproxy device, deleting a physical interface corresponding to theinterface identifier from a physical interface partition correspondingto a current virtual network identifier; and adding the physicalinterface to a physical interface partition corresponding to the targetvirtual network identifier.
 4. The configuration method of claim 1,wherein the process of setting up the mapping relation between thetarget virtual network and the interface comprises: by the communicationproxy device, deleting a virtual interface corresponding to theinterface identifier from a virtual interface partition corresponding toa current virtual network identifier; and modifying information about amapping relation between a physical interface partition corresponding tothe target virtual network identifier and the virtual interfacepartition.
 5. The configuration method of claim 1, wherein: thecommunication proxy device and an access device are set in a samephysical entity; or the communication proxy device is set in an accessconvergence device; or the communication proxy device and the servingedge device are set in a same physical entity.
 6. The configurationmethod of claims 1, wherein: the interface is a physical port, and theinformation about the mapping relation between the target virtualnetwork and the interface comprises the target virtual networkidentifier and a corresponding physical port identifier; or theinterface is a physical access circuit, and the information about themapping relation between the target virtual network and the interfacecomprises the target virtual network identifier and a correspondingphysical access circuit identifier; or the interface is a virtual port,and the information about the mapping relation between the targetvirtual network and the interface comprises a virtual target virtualnetwork identifier and a corresponding virtual port identifier; orcomprises the virtual target virtual network identifier and thecorresponding information about the mapping relation between the virtualport and the physical port; or the interface corresponding to the accessdevice is a virtual access circuit, and the information about themapping relation between the target virtual network and the interfacecomprises the virtual target virtual network identifier and acorresponding virtual access circuit identifier; or comprises thevirtual target virtual network identifier and the correspondinginformation about the mapping relation between the virtual port and thephysical port, wherein: the virtual network may be a Virtual Local AreaNetwork (VLAN) or a Virtual Private Network (VPN).
 7. A communicationsystem, comprising: a serving edge device, adapted to: obtain a targetvirtual network identifier and a corresponding interface identifier in aLayer-2 Control (L2C) protocol packet, generate an L2C protocol packet,and send the generated L2C protocol packet to an access network device;and a communication proxy device, adapted to: receive the L2C protocolpacket, obtain the target virtual network identifier and thecorresponding interface identifier from the L2C protocol packet, and setup a mapping relation between an interface corresponding to theinterface identifier and a target virtual network.
 8. A communicationproxy apparatus, comprising: a receiving unit, adapted to receive aLayer-2 Control (L2C) protocol packet that carries a target virtualnetwork identifier and a corresponding interface identifier; anobtaining unit, adapted to parse the L2C protocol packet to obtain thetarget virtual network identifier and the corresponding interfaceidentifier from the packet; a storing unit, adapted to: storeinformation about a mapping relation between an interface and a virtualnetwork, wherein the information about the mapping relation comprisesthe virtual network identifier and the interface identifier; and aconfiguring unit, adapted to modify the information about the mappingrelation in the storing unit according to obtained target virtualnetwork identifier and corresponding interface identifier.
 9. Thecommunication proxy apparatus of claim 8, wherein: the storing unitrecords at least one mapping relation partition information unit, andeach mapping relation partition information unit corresponds to avirtual network, and records the virtual network identifier and thecorresponding interface partition information; and the configuring unitdeletes interface information corresponding to the interface identifierfrom the mapping relation partition information unit corresponding to acurrent virtual network identifier, and adds the interface informationcorresponding to the interface identifier to the mapping relationpartition information unit corresponding to the target virtual networkidentifier.
 10. The communication proxy apparatus of claim 9, wherein:the interface is a physical interface, and the mapping relationpartition information unit records a virtual network identifier and thecorresponding physical interface information; or the interface is avirtual interface, and the mapping relation partition information unitrecords a logical virtual network identifier and the correspondingmapping relation between the virtual interface and the physicalinterface.
 11. The communication proxy apparatus of claim 10, furthercomprising: a port mapping unit, adapted to perform conversion betweenthe physical interface and the virtual interface for the received packetaccording to the information about the mapping relation between thephysical interface and the virtual interface.
 12. The communicationproxy apparatus of claim 8, further comprising: a matching unit, adaptedto: check whether the target virtual network identifier matches acurrent virtual network identifier; and, if they do not match, notifythe configuring unit to start configuration.